Subspecies: Only the maritima subspecies occurs in the Maritimes. Described in 1985, this subspecies is otherwise limited to Maine and the Gaspé Peninsula.

Notes: This species is found a variety of open, often disturbed, habitats, from roadsides to old fields and the edges of salt marshes where Beach Pea (Lathyrus japonicus) grows. It is highly localized, often occupying only small areas of much larger fields.